Intergas Boiler Error Code 1
Code 1 means the boiler cannot get rid of its heat. The usual causes are air in the system, low water pressure or a pump that is not running properly. Bleeding, topping up and resetting often solves it; if the code keeps coming back, an installer must check the pump and the flow.
Also shown as: 01
Applies to: Intergas HRE and Kombi Kompakt
Common causes
- Air in the central heating system, so the water does not circulate properly
- Circulation pump faulty, stuck or not running
- Insufficient flow through the heat exchanger, for example because radiator valves or isolation valves are closed
What to check, in order
- Open all radiator valves and bleed the boiler and the system.
- Check the water pressure on the display or pressure gauge and top up to 1.5 to 2 bar if needed.
- Press the reset button to restart the boiler.
- If the code returns, call a certified installer; the pump and the flow must be checked.
Clear the code and test
- Fix what the checks above found first — pressure topped up, a radiator bled, the thermostat set right. Resetting without fixing the cause only brings the code back.
- Make sure the boiler has power and the gas tap at the boiler is open.
- If the water pressure is below 1.5 bar, top it up to between 1.5 and 2 bar with the filling loop, as your manual shows.
- Press the reset button once and watch a full cycle: the boiler should start, heat the radiators or the tap water, and keep running without the code coming back.
When to call a professional
Most cases are solved by the checks above. Book a technician if any of these apply:
- The code comes back after you have run the checks and a test cycle.
- You smell burning, see sparks or scorch marks, or the breaker trips.
- Water is leaking and you cannot stop it.
- The fix needs panels opened beyond what your manual describes, or a part tested with a meter, and you are not set up for that.
When you call, give the brand, the code 1, your model number (on a label on the type plate, usually at the bottom or on the side of the boiler) and the checks you already ran. It shortens the visit.
Parts that may be involved
Circulation pump
Parts are model-specific. Find your model number first — usually on a label on the type plate, usually at the bottom or on the side of the boiler — and match the part to that number before ordering.
Questions people ask about 1
What does 1 mean on a Intergas boiler?
1 means: The boiler gets too hot: the heat cannot be carried away (insufficient flow). Code 1 means the boiler cannot get rid of its heat. The usual causes are air in the system, low water pressure or a pump that is not running properly. Bleeding, topping up and resetting often solves it; if the code keeps coming back, an installer must check the pump and the flow.
Can I fix Intergas 1 myself?
Start yourself: the checks on this page cover the causes you can reach without opening the machine up. If they point to a faulty part, testing or replacing it is usually a technician job.
How do I clear Intergas 1?
Fix what the checks above found first — pressure topped up, a radiator bled, the thermostat set right. Resetting without fixing the cause only brings the code back. Make sure the boiler has power and the gas tap at the boiler is open. If the water pressure is below 1.5 bar, top it up to between 1.5 and 2 bar with the filling loop, as your manual shows.
Sources checked
- Intergas HRE Parameter List / Fault Finding (manufacturer document)
- Warmgarant: Intergas storingscodes
The meaning and checks for this code were checked against the sources above in November 2026. Codes vary by model and region; if your manual lists a different meaning for your exact model, follow the manual.